JLox an Interpreter using Abstract Syntax Trees.

JLOX is a based Lox Programming language. Implemented using recursive descent parsing and runs on the Java Virtual Machine (JVM).Details the grammar, evaluation model, and execution workflow of JLOX.

Introduction

Features

Dynamic Typing: Variables can hold any type at runtime.

Garbage Collection: Managed by the JVM.

Lexical Scoping: Variables are scoped within blocks.

Functions as First-Class Citizens: Functions can be assigned to variables, passed as arguments, and returned.

Lox Programming language

Lexical Analysis

The Scanner converts source code into tokens.

var x = 10;

Produces tokens -

VAR IDENTIFIER( x ) EQUAL NUMBER( 10 ) SEMICOLON

Parsing (Abstract Syntax Tree)

The Parser constructs an AST from tokens.

Example AST for var x = 10;:

VarDecl(
  name = "x",
  initializer = Literal(10)
)

Semantic Analysis

Resolves variable scope

Validates function calls

Interpretation (Execution)

The Interpreter walks the AST and executes code.

print x;
Would produce output:
10

Syntax

Variables

var x = 10;
var name = "Alice";

Control Flow

If-Else
if (x > 5) {
    print "Greater than 5";
} else {
    print "Not greater than 5";
}

Loops

while (x < 20) {
    print x;
    x = x + 1;
}

Functions

fun greet(name) {
    print "Hello, " + name;
}
greet("Alice");

Contributing

Fork this repository.

Acknowledgement

Book - Crafting Interpreters by Robert Nystrom

License

MIT